OMEZ Capsule

- hypersensitivity to omeprazole, substituted benzimidazoles or to any of the excipients,

- omeprazole like other PPIs must not be used concomitantly with nelfinavir.

Side effects

The most common side effects (1-10% of patients) are headache, abdominal pain, constipation, diarrhoea, flatulence, nausea/vomiting.

Blood and lymphatic system disorders

Rare: leukopenia, thrombocytopenia

Very rare: agranulocytosis, pancytopenia

Immune system disorders

Rare: hypersensitivity reactions e.g. fever, angioedema and anaphylactic reaction/shock

Metabolism and nutrition disorders

Rare: hyponatraemia

Not known: hypomagnesaemia, severe hypomagnesaemia may result in hypocalcaemia. Hypomagnesaemia may also be associated with hypokalaemia.

Psychiatric disorders

Uncommon: insomnia

Rare: agitation, confusion, depression

Very rare: aggression, hallucination

Nervous system disorders

Common: headache

Uncommon: dizziness, paraesthesia, somnolence

Eye disorders

Rare: blurred vision

Ear and labyrinth disorders

Uncommon: vertigo

Respiratory, thoracic and mediastinal disorders

Rare: bronchospasm

Gastrointestinal disorders

Common: abdominal pain, constipation, diarrhoea, flatulence, nausea, vomiting

Rare: dry mouth, stomatitis, gastrointestinal candidiasis

Not known: microscopic colitis

Hepatobiliary disorders

Uncommon: increased liver enzymes

Rare: hepatitis with or without jaundice

Very rare: hepatic failure, encephalopathy in patients with pre-existing liver disease

Skin and subcutaneous tissue disorders

Uncommon: dermatitis, pruritus, rash, urticaria

Rare: alopecia, photosensitivity

Very rare: erythema multiforme, Stevens-Johnson syndrome, toxic epidermal necrolysis (TEN)

Musculoskeletal and connective tissue disorders

Uncommon: hip fracture, wrist fracture, spinal fracture

Rare: arthralgia, myalgia

Very rare: muscular weakness

Renal and urinary disorders

Rare: interstitial nephritis

Reproductive system and breast disorders

Very rare: gynaecomastia

General disorders and administration site conditions

Uncommon: malaise, peripheral oedema

Rare: increased sweating

Paediatric population: See package insert.

Active substances with pH dependent absorption

The decreased intragastric acidity during treatment with omeprazole might increase or decrease the absorption of active substances with a gastric pH dependent absorption.

Nelfinavir, atazanavir, Digoxin, Clopidogrel, Posaconazole, erlotinib, ketoconazole, itraconazole

Active substances metabolized by CYP2C19

The metabolism of concomitant active substances also metabolized by CYP2C19 may be decreased and the systemic exposure to these substances increased.

Cilostazol, phenytoin,

Unknown mechanism

Saquinavir, Methotrexate, Tacrolimus

Inhibitors CYP2C19 and/or CYP34

Active substances known to inhibit CYP2C19 or CYP3A4 may lead to increased omeprazole serum levels by decreasing omeprazole’s rate of metabolism.

Clarithromycin, voriconazole

Induces of CYP2C19 and/or 3A4

Active substances known to induce CYP2C19 or CYP3A4 may lead to decreased omeprazole serum levels by increasing omeprazole’s rate of metabolism.

Rifampicin, St John’s wort

Pregnancy

Omeprazole can be used during pregnancy.

Lactation

Omeprazole is excreted in breast milk but is not likely to influence the child when therapeutic doses are used.

Precautions

Gastric malignancy

In the presence of any alarm symptom (e.g. significant unintentional weight loss recurrent vomiting, dysphagia, haematemesis or melena) and when gastric ulcer is suspected or present, malignancy should be excluded, as treatment may alleviate symptoms and delay diagnosis.

Vitamin B12 absorption

Omeprazole may reduce the absorption of Vitamin B12 due to hypo- or achlorhydria. This should be considered in patients with reduced body stores or risk factors for reduced vitamin B12 absorption on long-term therapy.

Children with chronic illnesses

Some children with chronic illnesses may require long-term treatment although it is not recommended.

Risk of gastrointestinal infections

Treatment with PPI may lead to slightly increased risk of gastrointestinal infections such as Salmonella and Campylobacter. PPI therapy may also be associated with an increased risk of Clostridium difficile-associated diarrhoea (CDAD). A diagnosis of CDAD should be considered for patients taking PPIs who develop diarrhoea that does not improve. Symptoms include watery stool, abdominal pain and fever, which may develop into more serious intestinal conditions. Factors that may predispose an individual to developing CDAD include advanced age, certain chronic medical conditions and taking broad spectrum antibiotics. Patients should use the lowest dose and shortest duration of PPI therapy appropriate to the condition being treated.

Risk of hip, wrist and spine fracture

PPIs, especially if used in high doses and over long durations (>1year), may modestly increase the risk of hip, wrist and spine fracture, predominantly in the elderly or in presence of other recognized risk factors.

Exceeding a treatment

When exceeding a treatment period of 1 year, patients should be kept under regular surveillance.

Hypomagnesaemia

For patients expected to be on prolonged treatment or who take PPIs with digoxin or drugs that may cause hypomagnesaemia (e.g., diuretics), health care professionals should consider measuring magnesium levels before starting PPI treatment and periodically during treatment.

Interference with laboratory tests

Increased chromogranin A (CgA) levels may interfere with investigations for neuroendocrine tumours. To avoid this interference the omeprazole treatment should be temporarily stopped 5 days before CgA measurements.

Sucrose, Lactose

capsules contain sucrose and lactose.

Omeprazole, a racemic mixture of two enantiomers reduces gastric acid secretion through a highly targeted mechanism of action. It is a specific inhibitor of the acid pump in the parietal cell. It is rapidly acting and provides control through reversible inhibition of gastric acid secretion with once daily dosing.

Omeprazole is a weak base and is concentrated and converted to the active form in the highly acidic environment of the intracellular canaliculi within the parietal cell, where it inhibits the enzyme H+K+-ATPase- the acid pump. This effect on the final step of the gastric acid formation process is dose-dependent and provides for highly effective inhibition of both basal acid secretion and stimulated acid secretion, irrespective of stimulus.